The objective of this research is to study the mechanisms of action of three antineoplastic drugs which are presently in clinical trial or current therapy regimens. The agents are: Dimethyl triazeno imidazole carboxamide (DIC), Bleomycin, and Inosine diglycolaldehyde. The biochemical mode of action of these drugs on sensitive and resistant strains of Chinese hamster ovary cells, as well as other mammalian cell lines, will be examined.